Making and Breaking
Web Services
(with Ruby)
Chris Wanstrath
Err Free
http://errfree.com

ttp://farm1.static.flickr.com/138/320699460_b8e7c1e7e6_o.jpg

SOAP
• Simple Object Access Protocol?
• Lies.
• Service Oriented Architecture Protocol
• wtf.

Newsletters!

“Outbound”
• Slow response time
• Duplication of data
• Hard to debug
• require ‘soap/wsdlDriver’

Ruby SOAP Library:
Your Friend
• Creates methods on the fly
• Seems to work pretty well
• Transparently converts Ruby types to SOAP
definitions

Ruby SOAP Library:
Your Enemy
• Hard to debug (dump req/res to file)
• No one has ever used it
• There are not any alternatives
• The code is a jungle

Why use SOAP?
• One reason: legacy.

Wrapping SOAP
def update_user(email, subs = [], unsubs = [])
client.updateUser(brand, email, email, demo, subs, unsubs)
end

Wrapping SOAP
def update_user(email, subs = [], unsubs = [])
client.updateUser(brand, email, email, demo, subs, unsubs)
end
def get_user(email)
client.getUser(email, brand)
end

Wrapping SOAP
def update_user(email, subs = [], unsubs = [])
client.updateUser(brand, email, email, demo, subs, unsubs)
end
def get_user(email)
client.getUser(email, brand)
end

Wrapping SOAP
def update_user(email, subs = [], unsubs = [])
client.updateUser(brand, email, email, demo, subs, unsubs)
end
def get_user(email)
client.getUser(email, brand)
end

Testing SOAP
• Use mocks
• Mocha: http://mocha.rubyforge.org

Testing SOAP
def test_get_user_should_hit_client
email = 'chrisw@nstrath.com'
Outbound.client.expects(:getUser).with(email, Outbound.brand)
Outbound.get_user(email)
end

Testing SOAP
soap_methods = {
:getUser => true,
:updateUser => true
}
Outbound.stubs(:client).returns(mock('SOAP Service', soap_methods))

Running a SOAP Server
in Ruby

Just Kidding

Microformats!
• Your website is your API
• Plant classes in HTML
• Tell parsers what information is important
• http://microformats.org

hReview

hReview
<div id="review_16873" class="hreview">
<h5 class="item"><span class="fn">Beringer California Collection White Merlot 20
<abbr class="dtreviewed" title="20070420">(1 day ago)</abbr>
<span class="reviewer vcard">
<img class="photo" src="/assets/avatars/c19d1b2080f73765d420b461d3133ffa.jpg"
<a class="url fn" href="/people/garyvaynerchuk">garyvaynerchuk</a>
</span>
<abbr class="rating" title="50.0">50.0<em>/100</em></abbr>
<blockquote class="description">Had this in an industry event the other day, man
<p class="tags">Tasting Tags:
<a href="/tags/pink" rel="tag" class="rel-tag" title="view all wines with this t
<a href="/tags/sugar" rel="tag" class="rel-tag" title="view all wines with this
</p>
</div>

hReview
<div id="review_16873" class="hreview">
<h5 class="item"><span class="fn">Beringer California Collection White Merlot 20
<abbr class="dtreviewed" title="20070420">(1 day ago)</abbr>
<span class="reviewer vcard">
<img class="photo" src="/assets/avatars/c19d1b2080f73765d420b461d3133ffa.jpg"
<a class="url fn" href="/people/garyvaynerchuk">garyvaynerchuk</a>
</span>
<abbr class="rating" title="50.0">50.0<em>/100</em></abbr>
<blockquote class="description">Had this in an industry event the other day, man
<p class="tags">Tasting Tags:
<a href="/tags/pink" rel="tag" class="rel-tag" title="view all wines with this t
<a href="/tags/sugar" rel="tag" class="rel-tag" title="view all wines with this
</p>
</div>

mofo
$ sudo gem install mofo
Successfully installed mofo-0.2.2
$ irb -rubygems
>> require 'mofo/hreview'
=> true
>> review = HReview.find :first => 'http://corkd.com/wine/view/21670'
=> #<HReview:0x1598d04 ...>
>> review.properties
=> ["description", "item", "dtreviewed", "tags", "rating", "reviewer"]
>> review.rating
=> 50.0
>> review.item.fn
=> "Beringer California Collection White Merlot 2005"
>> review.reviewer.fn
=> "garyvaynerchuk"

mofo/hreview.rb
class HReview < Microformat
one :version, :summary, :type, :dtreviewed,
:rating, :description
one :reviewer => HCard
one :item! do
one :fn
end
end

microformat.rb
def collector
collector = Hash.new([])
def collector.method_missing(method, *classes)
super unless %w(one many).include? method.to_s
self[method] += Microformat.send(:break_out_hashes, classes)
end
collector
end

mofo supports...
• xoxo
• hCard
• geo
• hCalendar
• adr
• hReview
• xfn
• hEntry
• hResume

What else can they do?

Operator

Operator

Okay.

Hpricot
( by _why )

Hpricot
$ irb -rubygems -r'open-uri'
>> require 'hpricot'
=> true
>> page = Hpricot open('http://google.com')
=> #<Hpricot::Doc ...>
>> page.search(:a).size
=> 20
>> page.at(:a)
=> {elem <a href="/url?sa=p&pref=ig&pval=3
&q=http://www.google.com/ig%3Fhl%3Den&usg=
AFrqEzfPu3dYlSVsfjI7gUHePgEkcx_VXg">
"Personalize this page" </a>}

Hpricot
Can use XPATH, CSS selectors, whatever, to search

Hpricot
>> page = Hpricot(open('http://brainspl.at'))
=> #<Hpricot::Doc ...>
>> page.search('.post').size
=> 10

Hpricot
>> corkd = 'http://corkd.com/wine/view/21670'
=> 'http://corkd.com/wine/view/21670'
>> page = Hpricot(open(corkd))
=> #<Hpricot::Doc ...>
>> page.search('.hreview').size
=> 4

Hpricot/:mofo
>> page.at('.hreview').at('.item').at('.fn').inner_text
=> "Beringer California Collection White Merlot 2005"
>> review.item.fn
=> "Beringer California Collection White Merlot 2005"

Oh, you can use Hpricot
for XML, too.
<Export>
<Product>
<SKU>403276</SKU>
<ItemName>Trivet</ItemName>
<CollectionNo>0</CollectionNo>
<Pages>0</Pages>
</Product>
</Export>

Oh, you can use Hpricot
for XML, too.
fields = %w(SKU ItemName CollectionNo Pages)
doc = Hpricot(open("my.xml"))
(doc/:product).each do |xml_product|
attributes = fields.inject({}) do |hash, field|
hash.merge(field => xml_product.at(field).innerHTML)
end
Product.create(attributes)
end
( also there’s Hpricot::XML() )

But who uses XML?

Cheat!
http://cheat.errtheblog.com
(insert short, live demo here)

Thanks
• http://mofo.rubyforge.org
• http://code.whytheluckystiff.net/hpricot
• https://addons.mozilla.org/en-US/firefox/addon/4106
• http://microformats.org
• http://upcoming.yahoo.com/
• http://corkd.com/
• http://chow.com
• http://chowhound.com

Thanks
• http://ronrothman.com/gallery/cnet/cnet_neon
• http://flickr.com/photos/bootbearwdc/466751240/
• http://flickr.com/photos/segana/320699460/
• http://flickr.com/photos/spiffariffic/456211526/